How to Calculate Startup Equity Vesting
In this guide:
Understanding Startup Equity and Stock Options
Whether you are a founder preparing to issue shares or an early employee evaluating a job offer, understanding the math behind equity is absolutely crucial.
Stock options represent a percentage of ownership in a company, but their true monetary value depends on several complex factors: the company's current valuation, your strike price, the total number of outstanding shares, and inevitable dilution from future funding rounds.
What is a Vesting Schedule?
It's important to know that most startup equity doesn't belong to you immediately upon signing your contract. It is subject to what is called a 'vesting schedule.'
The industry standard in tech is a 4-year vest with a 1-year cliff. This means if you leave the company before 12 months, you get absolutely nothing. However, on your exact 1-year anniversary (the cliff), 25% of your total shares vest immediately. Afterward, the remaining shares vest incrementally every single month for the next three years.
How to Use the Equity Calculator to Forecast Value
- Input Your Option Grant—Enter the total number of options granted to you in your offer letter.
- Set the Timeline—Define your specific vesting schedule (e.g., a standard 48 months).
- Add Valuation Data—Input the current estimated company valuation and your strike price to accurately model the potential monetary value of your equity.
- Visualize Your Future—View the interactive chart to see exactly how many shares you will own, and what they might be worth, at any given month in the future.
The Impact of Dilution
As your company grows and raises more venture capital (Series A, Series B, etc.), new shares are created and issued to investors. This increases the total pie, but it means your specific slice of the pie becomes a smaller percentage.
Our tool helps you model this dilution so you can set realistic expectations about the final payout of your options during an acquisition or IPO.
Frequently Asked Questions
What is a standard equity vesting schedule?
What does equity dilution mean?
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